Take a look at these threads:

Rear sub frame Bushings W126 1985 300SD DIY
http://www.peachparts.com/shopforum/diesel-discussion/112850-rear-sub-frame-bushings-w126-1985-300sd-diy.html#post796976

Anyone ever broke a rear subframe bushing bolt?
http://www.peachparts.com/shopforum/diesel-discussion/73580-anyone-ever-broke-rear-subframe-bushing-bolt.html#post461406

W126 subframe mount clarification needed
http://www.peachparts.com/shopforum/tech-help/60587-w126-subframe-mount-clarification-needed.html#post370569

W126 Ride quality
http://www.peachparts.com/shopforum/tech-help/84033-w126-ride-quality.html#post543139

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Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
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1985 300SD
1983 300D
2003 Volvo V70

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